drm/i915: split out i915_reg_read_ioctl() to i915_ioctl.[ch]

Add new files i915_ioctl.[ch] to hold small ioctls that are out of place
everywhere else, and not big enough to warrant a file of their own. For
starters, it's just for i915_reg_read_ioctl() that's a bit high level
for a low level implementation that intel_uncore.[ch] is.

Suggested-by: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220120113346.3214745-1-jani.nikula@intel.com

drivers/gpu/drm/i915/Makefile

@@ -32,8 +32,9 @@ subdir-ccflags-y += -I$(srctree)/$(src)
 # core driver code
 i915-y += i915_driver.o \
 	  i915_config.o \
-	  i915_irq.o \
 	  i915_getparam.o \
+	  i915_ioctl.o \
+	  i915_irq.o \
 	  i915_mitigations.o \
 	  i915_module.o \
 	  i915_params.o \

drivers/gpu/drm/i915/i915_driver.c

@@ -76,6 +76,7 @@
 #include "i915_drv.h"
 #include "i915_getparam.h"
 #include "i915_ioc32.h"
+#include "i915_ioctl.h"
 #include "i915_irq.h"
 #include "i915_memcpy.h"
 #include "i915_perf.h"

drivers/gpu/drm/i915/i915_drv.h

@@ -1716,9 +1716,6 @@ mkwrite_device_info(struct drm_i915_private *dev_priv)
 	return (struct intel_device_info *)INTEL_INFO(dev_priv);
 }
 
-int i915_reg_read_ioctl(struct drm_device *dev, void *data,
-			struct drm_file *file);
-
 static inline int intel_hws_csb_write_index(struct drm_i915_private *i915)
 {
 	if (GRAPHICS_VER(i915) >= 11)

drivers/gpu/drm/i915/i915_ioctl.c

@@ -0,0 +1,94 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright © 2022 Intel Corporation
+ */
+
+#include "gt/intel_engine_regs.h"
+
+#include "i915_drv.h"
+#include "i915_gem.h"
+#include "i915_ioctl.h"
+#include "i915_reg.h"
+#include "intel_runtime_pm.h"
+#include "intel_uncore.h"
+
+/*
+ * This file is for small ioctl functions that are out of place everywhere else,
+ * and not big enough to warrant a file of their own.
+ *
+ * This is not the dumping ground for random ioctls.
+ */
+
+struct reg_whitelist {
+	i915_reg_t offset_ldw;
+	i915_reg_t offset_udw;
+	u8 min_graphics_ver;
+	u8 max_graphics_ver;
+	u8 size;
+};
+
+static const struct reg_whitelist reg_read_whitelist[] = {
+	{
+		.offset_ldw = RING_TIMESTAMP(RENDER_RING_BASE),
+		.offset_udw = RING_TIMESTAMP_UDW(RENDER_RING_BASE),
+		.min_graphics_ver = 4,
+		.max_graphics_ver = 12,
+		.size = 8
+	}
+};
+
+int i915_reg_read_ioctl(struct drm_device *dev,
+			void *data, struct drm_file *unused)
+{
+	struct drm_i915_private *i915 = to_i915(dev);
+	struct intel_uncore *uncore = &i915->uncore;
+	struct drm_i915_reg_read *reg = data;
+	struct reg_whitelist const *entry;
+	intel_wakeref_t wakeref;
+	unsigned int flags;
+	int remain;
+	int ret = 0;
+
+	entry = reg_read_whitelist;
+	remain = ARRAY_SIZE(reg_read_whitelist);
+	while (remain) {
+		u32 entry_offset = i915_mmio_reg_offset(entry->offset_ldw);
+
+		GEM_BUG_ON(!is_power_of_2(entry->size));
+		GEM_BUG_ON(entry->size > 8);
+		GEM_BUG_ON(entry_offset & (entry->size - 1));
+
+		if (IS_GRAPHICS_VER(i915, entry->min_graphics_ver, entry->max_graphics_ver) &&
+		    entry_offset == (reg->offset & -entry->size))
+			break;
+		entry++;
+		remain--;
+	}
+
+	if (!remain)
+		return -EINVAL;
+
+	flags = reg->offset & (entry->size - 1);
+
+	with_intel_runtime_pm(&i915->runtime_pm, wakeref) {
+		if (entry->size == 8 && flags == I915_REG_READ_8B_WA)
+			reg->val = intel_uncore_read64_2x32(uncore,
+							    entry->offset_ldw,
+							    entry->offset_udw);
+		else if (entry->size == 8 && flags == 0)
+			reg->val = intel_uncore_read64(uncore,
+						       entry->offset_ldw);
+		else if (entry->size == 4 && flags == 0)
+			reg->val = intel_uncore_read(uncore, entry->offset_ldw);
+		else if (entry->size == 2 && flags == 0)
+			reg->val = intel_uncore_read16(uncore,
+						       entry->offset_ldw);
+		else if (entry->size == 1 && flags == 0)
+			reg->val = intel_uncore_read8(uncore,
+						      entry->offset_ldw);
+		else
+			ret = -EINVAL;
+	}
+
+	return ret;
+}

drivers/gpu/drm/i915/i915_ioctl.h

@@ -0,0 +1,14 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright © 2022 Intel Corporation
+ */
+
+#ifndef __I915_IOCTL_H__
+#define __I915_IOCTL_H__
+
+struct drm_device;
+struct drm_file;
+
+int i915_reg_read_ioctl(struct drm_device *dev, void *data, struct drm_file *file);
+
+#endif /* __I915_IOCTL_H__ */

drivers/gpu/drm/i915/intel_uncore.c

@@ -2265,76 +2265,6 @@ void intel_uncore_fini_mmio(struct intel_uncore *uncore)
 	uncore_mmio_cleanup(uncore);
 }
 
-static const struct reg_whitelist {
-	i915_reg_t offset_ldw;
-	i915_reg_t offset_udw;
-	u8 min_graphics_ver;
-	u8 max_graphics_ver;
-	u8 size;
-} reg_read_whitelist[] = { {
-	.offset_ldw = RING_TIMESTAMP(RENDER_RING_BASE),
-	.offset_udw = RING_TIMESTAMP_UDW(RENDER_RING_BASE),
-	.min_graphics_ver = 4,
-	.max_graphics_ver = 12,
-	.size = 8
-} };
-
-int i915_reg_read_ioctl(struct drm_device *dev,
-			void *data, struct drm_file *file)
-{
-	struct drm_i915_private *i915 = to_i915(dev);
-	struct intel_uncore *uncore = &i915->uncore;
-	struct drm_i915_reg_read *reg = data;
-	struct reg_whitelist const *entry;
-	intel_wakeref_t wakeref;
-	unsigned int flags;
-	int remain;
-	int ret = 0;
-
-	entry = reg_read_whitelist;
-	remain = ARRAY_SIZE(reg_read_whitelist);
-	while (remain) {
-		u32 entry_offset = i915_mmio_reg_offset(entry->offset_ldw);
-
-		GEM_BUG_ON(!is_power_of_2(entry->size));
-		GEM_BUG_ON(entry->size > 8);
-		GEM_BUG_ON(entry_offset & (entry->size - 1));
-
-		if (IS_GRAPHICS_VER(i915, entry->min_graphics_ver, entry->max_graphics_ver) &&
-		    entry_offset == (reg->offset & -entry->size))
-			break;
-		entry++;
-		remain--;
-	}
-
-	if (!remain)
-		return -EINVAL;
-
-	flags = reg->offset & (entry->size - 1);
-
-	with_intel_runtime_pm(&i915->runtime_pm, wakeref) {
-		if (entry->size == 8 && flags == I915_REG_READ_8B_WA)
-			reg->val = intel_uncore_read64_2x32(uncore,
-							    entry->offset_ldw,
-							    entry->offset_udw);
-		else if (entry->size == 8 && flags == 0)
-			reg->val = intel_uncore_read64(uncore,
-						       entry->offset_ldw);
-		else if (entry->size == 4 && flags == 0)
-			reg->val = intel_uncore_read(uncore, entry->offset_ldw);
-		else if (entry->size == 2 && flags == 0)
-			reg->val = intel_uncore_read16(uncore,
-						       entry->offset_ldw);
-		else if (entry->size == 1 && flags == 0)
-			reg->val = intel_uncore_read8(uncore,
-						      entry->offset_ldw);
-		else
-			ret = -EINVAL;
-	}
-
-	return ret;
-}
-
 /**
  * __intel_wait_for_register_fw - wait until register matches expected state
  * @uncore: the struct intel_uncore